Heh, I rather like the idea of the stone messing around with its wishers, though not necessarily maliciously.
Anyway, hope you like the addition. I'm working on the premise that Princess the mermaid really was an animal in the new past. The addition of Jon's mind simply boosted her intelligence and self-awareness. So, the new and improved Princess may catch a few people off-guard.
As for whether this breaks the rule of the stone's changes being "as if they had always been so," oh well. Such a thing seems way too vague for me (thanks for nothing, Jon's grandfather). I prefer to think that the stone just edits out its own involvement, sometimes by changing history, altering people, even making additional magical objects (scapegoats).
